GarrettCom Magnum 3000 - Manual (Page 26)

Magnum 3000 Stackable Hubs Installation and User Guide (07/06)
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1. Before connecting the fiber optic cable, remove the protective dust caps from the
tips of the connectors on the PM-ST. Save these dust caps for future use.
2. Wipe clean the ends of the dual connectors with a soft cloth or lint-free lens tissue
dampened in alcohol. Make certain the connectors are clean before connecting.
Note:
One strand of the duplex fiber optic cable is coded using color bands
at regular intervals; you must use the color-coded strand on the
associated ports at each end of the fiber optic segment.
3. Connect the Transmit (TX) port (light colored post) on the Magnum PM-FST to
the Receive (RX) port of the remote device. Begin with the color-coded strand
of the cable for this first TX-to-RX connection.
4. Connect the Receive (RX) port (dark colored post) on the PM-FST to the (TX)
Transmit port of the remote device. Use the non-color coded fiber strand for this.
5. The LINK LED on the front of the PM-FST will illuminate when a proper
connection has been established at both ends (and when power is ON in the
unit). If LINK is not lit after cable connection, the normal cause is improper
cable polarity. Swap the fiber cables at the Port Module connector to remedy
this situation.
3.1.6 Connecting Fiber Optic (SC-type, "Snap-On")
The same five-step procedure as for fiber ST-type applies to FOIRL and
10BASE-FL applications using an RPM-SC card used with SC-type fiber connectors.
Follow the five steps as described in the Section 3.3.5 above.
When connecting fiber media to SC connectors, simply snap on the square
male connector into the SC female jack of the device until it clicks and secures.
3.1.7 Connecting Single-Mode Fiber Optic (SMF)
When using the RPM-SMF, be sure to use single-mode (small diameter) fiber
cable. The same five-step procedure as for multi-mode ST-type applies to single-mode.
3.1.8 Power Budget Calculations for Magnum 3000s RPM’s with Fiber
Media
Receiver Sensitivity and Transmitter Power are the parameters necessary to
compute the power budget. To calculate the power budget of different fiber media
installations using Magnum products, the following equations should be used:
OPB (Optical Power Budget) = P
T
(min) - P
R
(min)
where P
T
= Transmitter Output Power, and P
R
= Receiver Sensitivity
Worst case OPB = OPB - 1dB(for LED aging) - 1dB(for insertion loss)
Worst case distance = {Worst case OPB, in dB} / [Cable Loss, in dB/Km]
where the “Cable Loss” for 62.5/125 and 50/125 µm (M.m) is 2.8 dB/km,